1. Field of the Invention
The present invention relates to an electronic information authenticating system, portable information terminal, and an electronic information authenticating method to be used in the electronic information authenticating system and a portable information terminal and more particularly to security of an electronic ticket (admission ticket or a like) stored in the portable information terminal such as a portable cellular phone or a like.
The present application claims priority of Japanese Patent Application No. 2003-323835 filed on Sep. 17, 2003, which is hereby incorporated by reference.
2. Description of the Related Art
In recent years, a portable information terminal such as a portable cellular phone or a like, as it is made multifunctional, is used as a device to input, store, and output, a concert ticket, movie ticket, airline ticket, lodging ticket, resident's card, and admission ticket to an amusement park and/or entertainment facility, in a form of electronic data as so-called an electronic ticket.
When the portable information terminal is used as a device to store the electronic ticket, by presenting the electronic ticket appearing on its display section at a place where information contained in the ticket is required, for example, at an entrance of a concert hall, movie theater, amusement park, recreational facility or a like, permission is granted to enter these places.
However, such the conventional portable information terminal as above has a problem. That is, when the electronic ticket is managed by the conventional portable information terminal, as a ticket storing site which can retain an enhanced level of security, use of a special memory (hereinafter referred to as a “secure memory”) having a high level of security such as an IC (Integrated Circuit) card or a like being excellent in tamper-resistance is required, however, the use of such the secure memory causes high costs.
Also, when related information of the electronic ticket has to be stored, it is supposed that a memory is required which has a capacity being larger than that required to simply store original information (data) of a ticket itself. However, since a required level of security for the related information is comparatively low, an ordinary memory rather than the so-called secure memory is preferably used as a storing device. Even in this case, however, it is needless to say that some limitation on access to the ordinary memory is necessary.
Examples of storing such electronic related information in the secure memory or in the ordinary memory to which no limitation on access to the ordinary memory is imposed are disclosed in Japanese Patent Application Laid-open Nos. 2003-162602, 2002-324256, 2002-189933, 2002-140742, and 2002-83333. However, in the case of these examples disclosed, there is a danger that such the related information is easily deleted or tampered with by a malicious person.